1. Field of the Invention
The present invention relates to suture instruments that are used for endoscopically suturing tissue in the living body, especially to those suture instruments used in conjunction with flexible endoscopes.
2. Description of the Related Art
Currently, in many cases, in-vivo tissue of a patient is sutured through surgical operation. A surgical operation, however, is highly invasive because it naturally requires an incision to the patient body. Furthermore, it requires post-operative hospitalization, the cost of which can be a heavy burden for the patient. In these circumstances, the development of a low-invasive oral endoscopic procedure that eliminates the need for open surgery is anticipated.
For example, there is an instrument for suturing in-vivo tissue through an oral endoscopic, the arrangement of which has been disclosed in the U.S. Pat. No. 5,792,153. (See FIG. 22 through FIG. 26)
The instrument (a) which can be mounted on an endoscope, comprises a tube (b) that can be connected to the suction source, a cavity (c) to which the tube (b) is joined, a hollow needle (d) inserted in the forceps channel of the endoscope, a tag (g) provided with a lumen and side holes (e and f) that can be incorporated into the needle, a wire (i) with a valve (h) which can move back and forth in the needle (d) and can be mounted to the side hole (e) detachably, a thread (j) tied to the tag (g), and a grasping member (k) which is provided at the tip of the cavity (c) and is easily connected and disconnected to the side hole (f).
With the valve (h) joined to the side hole (e), the tag (g) is inserted into the needle (d). Then, an endoscope, with the instrument (a) mounted on it, is orally inserted into the patient lumen to suck the tissue (l) to be sutured into the cavity (c). The tissue (l) is then penetrated with the needle (d) that has been thrust out through the endoscope tip. Next, the wire (i) is pushed forward to thrust out the tag (g) through the needle (d) so that the side hole (f) of the tag (g) can be joined to the grasping member (k). The valve (h) is then removed from the side hole (e) so as to pull the wire (i) and the needle (d) into the endoscope. After this, suction is released.
Again, the tissue (l) is sucked into the cavity (c) to be penetrated with the needle (d). Then the valve (h) is joined to the side hole (e) and the grasping member (k) is removed from the opening (f). The valve (h), the tag (g) and the needle (d) are withdrawn and the suction is released. The steps above are repeated as many times as are necessary and then the instrument (a) is removed from the lumen together with the endoscope. When both ends of the thread, which have been pulled out from the body, are tied together and fixed, the suture procedure is terminated.
However, in the arrangement disclosed in U.S. Pat. No. 5,792,153, fine control of location of the penetration is very difficult because penetration is performed with the tissue placed inside the cavity. This will prevent the tissue from being securely sutured, or will require more stitches than necessary, resulting in extended operation time.
Moreover, inability to control the intervals between the stitches will prevent the tissue from being securely sutured with less number of stitches.
In addition, each penetration requires joining the valve (h) and the side hole (e) and releasing the grasping member (k) and the opening (f) and vice versa. These two operations, required per penetration, will make the treatment procedure very complicated, extending the treatment time as well.
Application of the procedure will be limited because the size of the cavity determines the area to penetrate at one time, making suture impossible when the suture area is too large to suck in the cavity. If the length or the height of the cavity is increased to hold more tissue to be sutured, there will inevitably be an increase in length and diameter of the instrument (a) itself, making it impossible to insert it into the body lumen or to locate the penetration for accurate suture. These can not only impose more burdens onto the patient at the time of its insertion but also possibly extend the treatment time.
The instrument (a) requires inserting the tag (g) into the needle (d) from the tip of the needle. This can accidentally cause the operator to prick his finger with the needle while he is trying to insert the tag into it.